Psychological Science, La Trobe University, Melbourne, Victoria, Australia.
J Int Neuropsychol Soc. 2010 Mar;16(2):342-51. doi: 10.1017/S1355617709991391.
In addition to deficits in delayed recall, recent research suggests that participants with amnestic mild cognitive impairment (aMCI) demonstrate diminished use of strategic encoding strategies during learning. Few studies have explored the cognitive mechanisms underlying this deficit. The aim of this study was to investigate in aMCI whether components of working memory (executive attention--attention set-shifting, dividing and focusing attention; and episodic buffer functions--strategic retrieval and manipulation of information) predict strategic encoding strategies during learning (semantic clustering). Thirty-three participants with aMCI and 33 healthy older adults (HOA) were administered neuropsychological tests assessing word-list learning and working memory. The aMCI group demonstrated significant impairment in acquisition, retrieval of information, and decreased use of semantic clustering strategies. Use of semantic clustering in the aMCI group was not predicted by measures of executive attention or phonemic verbal fluency, but was predicted by semantic verbal fluency performance. In the HOA group, semantic clustering was strongly related to semantic verbal fluency. These findings suggest that in aMCI, diminished strategic encoding strategies during learning (semantic clustering) is selectively related to the strategic function of the episodic buffer, but only when in interaction with the manipulation and retrieval of semantic associations.
除了延迟回忆缺陷外，最近的研究表明，遗忘型轻度认知障碍（aMCI）患者在学习过程中表现出策略性编码策略的使用减少。很少有研究探讨这种缺陷的认知机制。本研究旨在探讨 aMCI 患者的工作记忆成分（执行注意——注意定势转移、分配和集中注意；以及情景缓冲功能——策略性检索和信息操作）是否能预测学习过程中的策略性编码策略（语义聚类）。33 名 aMCI 患者和 33 名健康老年人（HOA）接受了单词列表学习和工作记忆的神经心理学测试。aMCI 组在获取、信息检索方面表现出明显的障碍，并且减少了语义聚类策略的使用。aMCI 组中语义聚类的使用与执行注意或语音流畅性无关，而是与语义流畅性表现相关。在 HOA 组中，语义聚类与语义流畅性高度相关。这些发现表明，在 aMCI 中，学习过程中策略性编码策略（语义聚类）的减少与情景缓冲的策略性功能有关，但仅在与语义联想的操作和检索相互作用时才有关。
